Vitamin D and Hypoxia-Inducible Factor (HIF-1α) Serum Levels as Markers for Progression of Nephropathy in Type 2 Diabetic Patients.

BACKGROUND: Vitamin D is a locally acting hormone, which plays a major role in skeletal health. Previous studies reported an important role of vitamin D in modulation of inflammatory response. We aimed to investigate the role of vitamin D deficiency and hypoxia-inducible factor (HIF-1α) as markers for the progression of diabetic nephropathy in Saudi patients with type 2 diabetes mellitus (T2DM). METHODS: We included 174 Saudi patients with T2DM in addition to 60 healthy control subjects. Patients were classified according to urinary Albumin to Creatinine Ratio (ACR) into three groups: Group AI: ACR < 30 µg/mg, Group AII: ACR levels of 30 - 300 µg/mg and Group AIII: ACR > 300 µg/mg. We estimated fasting blood glucose, HbA1c, lipid profile, serum creatinine, hemoglobin concentration (Hb), estimated glomerular filtration rate (eGFR), urine albumin/creatinine ratio, serum 25 hydroxyvitamin D, calcium, parathyroid hormone (PTH), tumor necrosis factor (TNF-α), C- reactive protein (CRP), and hypoxia-inducible factor (HIF-1α). RESULTS: There was a significant difference among studied groups regarding serum levels of vitamin D, calcium, PTH, TNF-α, CRP, and HIF-1α levels. The level of vitamin D was lower in diabetic patients in comparison to the controls and was significantly related to the severity of renal nephropathy as indicated by the level of albumin in urine. Moreover, vitamin D levels showed significant negative correlation with the inflammatory markers: TNF-α, CRP, and HIF-1α levels. CONCLUSIONS: Vitamin D deficiency and elevated HIF-1α serum levels showed a significant correlation to progression of nephropathy in Saudi patients with T2DM.

Association of Vitamin D Deficiency, Dyslipidemia, and Obesity with the Incidence of Coronary Artery Diseases in Type 2 Diabetic Saudi Patients.

BACKGROUND: Diabetes mellitus type 2 (T2DM) is a chronic metabolic disease associated with vascular complications. We aimed to evaluate the relationship of vitamin D deficiency, dyslipidemia, and obesity with the incidence of coronary artery disease in type 2 diabetes mellitus. METHODS: The study included 200 Saudi adult subjects, aged 40 - 60 years, of both genders, attending King Abdulaziz Specialist Hospital in Taif city. Subjects were divided into four groups; 50 subjects each: Control group, type 2 diabetic, type 2 diabetic with coronary artery disease, and type 2 diabetic obese patients having body mass index (BMI) ≥ 30 kg/m2. Serum vitamin D (25-OH-D), fasting blood glucose (FBG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglycerides (TG), and glycosylated hemoglobin (HbA1c) levels were estimated. RESULTS: Serum vitamin D and HDL-C in the three diabetic patient groups were significantly decreased (p < 0.001) compared to the control group. Among patient groups, the levels in the diabetic coronary and diabetic obese patients were significantly decreased as compared to the diabetic patient group (p < 0.001). FBG levels, HbA1c%, TC, TG, LDL-C levels, and BMI in all diabetic patient groups were significantly higher (p < 0.001) in comparison to control. Significant negative correlations were observed between serum vitamin D and FBG, HbA1c%, TC, TG, LDL-C levels, and BMI whereas positive correlations with HDL-C in all diabetic patient groups. CONCLUSIONS: The deficiency status of 25-OH-D is associated with dyslipidemia in type 2 Saudi diabetic patients, specifically those complicated with obesity and coronary artery diseases.

Association of Vitamin D Deficiency and Vitamin D Receptor Genetic Variants With Coronary Artery Disease in Type 2 Diabetic Saudi Patients.

BACKGROUND/AIM: Vitamin D deficiency accelerates the onset of type 2 diabetes mellitus (T2DM). Polymorphisms in the vitamin D receptor (VDR) have been linked to coronary artery disease (CAD). This study aimed to evaluate the association of vitamin D deficiency and VDR polymorphism with CAD in T2DM. PATIENTS AND METHODS: A total of 150 adult male and female subjects, aged from 40 to 60 years, were divided into three groups, each with 50 subjects; control group, T2DM, and T2DM with CAD. Fasting blood glucose (FBG), total cholesterol (TC), triglycerides (TG), HDL-C, LDL-C, glycosylated hemoglobin (HbA1c), and 25-hydroxyvitamin D (25-OH D) were assessed. VDR genotypes (BsmI, Taq1 and FOK1) were investigated by polymerase chain reaction fragment length polymorphism. RESULTS: There was a significant negative correlation between serum 25-OH D and FBG, TC, TG, and LDL-C levels, and a positive correlation with HDL-C levels in all diabetic patient groups. The risk of CAD was markedly higher in the group of T2DM with CAD in comparison to the control (p<0.0001) and the T2DM group. Regarding Taq1, there was also a significantly higher risk of CAD in Tt+tt genotypes and t allele in the T2DM with CAD group compared to control (p<0.001, 0.031 respectively). In addition, 25-OH D concentrations and the prevalence of VDR polymorphisms (BsmI, Taq1) were correlated with the risk of CAD. CONCLUSION: Deficiency of vitamin D and the prevalence of VDR polymorphisms (BsmI, Taq1) can serve as important markers for CAD.

Effect of Application of Treadmill Training on Metabolic Control and Vitamin D Level in Saudi Patients with Type 2 Diabetes Mellitus.

BACKGROUND: Diabetes mellitus type 2 and vitamin D deficiency are both prevalent in the Saudi Arabia. Vitamin D deficiency treatment with supplements carries a risk of intoxication. AIM: The present study is aimed at elucidating the effect of exercise on modulation of metabolic status and vitamin D level in patients with type 2 diabetes mellitus (T2DM). METHODS: A sum of 110 type 2 diabetic patients were voluntarily enrolled for the present investigation by dividing them into two separate groups (55 individuals for each group), the diabetic study group and diabetic control group. The diabetic study group was engaged in the training program using treadmill exercise. Laboratory parameters were monitored before and after the training program. RESULTS: There were significant elevation in the diabetic study group compared to diabetic control group regarding postexercise vitamin D level, high-density lipoprotein (HDL) (p value ≤ 0.001, 0.045; respectively). In addition, triglycerides, low-density lipoprotein (LDL), glycosylated hemoglobin (HbA1C), and homeostatic model assessment-insulin resistance (HOMA-IR) were significantly decreased (p value < 0.001 for all mentioned parameters). Moreover, there were significant higher level in postexercise parameters as compared to preexercise level in the diabetic study group. CONCLUSION: The exercise training program improved the metabolic control and vitamin D level after three months of intervention.